Bigger River Man

Slovenian superswimmer Martin Strel wants to tackle the Colorado.

FOLLOWING THE SUCCESS of the film Big River Man, which documented Martin Strel's 2007 epic down the Amazon River, the extra-large Slovenian has been trying to make bank, working the U.S. lecture circuit and hawking nutritional products, including a liver-detox tea. So when the History Channel proposed a made-for-TV swim last December, Strel, 56, was all in.

The result: starting on May 6, the happiest man in the water will swim 25 miles of the Colorado River, from the Glen Canyon Dam past Lees Ferry, with cameras rolling. As he did on the Amazon, Strel will wear a wetsuit and flippers and have a support team—this time a helicopter, kayak escorts, and a motor­ized boat. To prepare for the river's 50-degree temperatures, Strel spent more than a month training in San Francisco Bay's frigid, notoriously tough currents. Still, he has yet to tackle the sort of big, cold Class III rapids he'll encounter in the Colorado.

"It's not like swimming the crawl in the pool," says Strel, who will also wear an inflatable life vest. "You have to be like a plane. Sometimes you turn backward and use flippers when hands aren't strong enough." The other strategy Strel will adopt to enhance his performance: sobriety. The swimmer, known for favoring wine over energy drinks, will eschew alcohol altogether.

"Only red grapes," he says. "I must concentrate 100 percent. I don't want to die in the Colorado. It would be unprofessional and bad publicity for me." As always, Strel's swim is meant to raise awareness for clean water and world peace.